1. Field of the Invention
The invention relates to a vehicle including a secondary battery, and using electric power from the secondary battery as drive power.
2. Description of Related Art
Generally, a fuel cell vehicle includes a fuel cell and a secondary battery as electric power sources (Japanese Patent Application Publication No. 2010-279124 (JP 2010-279124 A) and Japanese Patent Application Publication No. 2002-008694 (JP 2002-008694 A)). The fuel cell vehicle usually uses the fuel cell as a main electric power source, and travels by using the output of the fuel cell. For example, when the output of the fuel cell cannot be changed in accordance with changes in the load, the shortfall in electric power is compensated for by the secondary battery. The secondary battery is charged with a portion of the output power of the fuel cell, regenerative electric power, etc.
A fuel cell vehicle can be caused to function as an electric power supply apparatus by connecting the secondary battery with an external load. However, since the amount of electricity generated by the fuel cell and the capacity of the secondary battery are limited, it is desirable that electric power from the secondary battery can be more efficiently supplied to the external load when the fuel cell vehicle is caused to function as a mobile electric power supply apparatus. This demand is not limited to the fuel cell vehicles but is also made with regard to other types of vehicles, such as hybrid vehicles and the like, which include a secondary battery as a subsidiary power source, and which are capable of functioning as an electric power supply apparatus for external loads.